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path: root/drivers/nvdimm/btt_devs.c
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Diffstat (limited to 'drivers/nvdimm/btt_devs.c')
-rw-r--r--drivers/nvdimm/btt_devs.c219
1 files changed, 50 insertions, 169 deletions
diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
index 6ac8c0fea..cb477518d 100644
--- a/drivers/nvdimm/btt_devs.c
+++ b/drivers/nvdimm/btt_devs.c
@@ -21,63 +21,13 @@
#include "btt.h"
#include "nd.h"
-static void __nd_btt_detach_ndns(struct nd_btt *nd_btt)
-{
- struct nd_namespace_common *ndns = nd_btt->ndns;
-
- dev_WARN_ONCE(&nd_btt->dev, !mutex_is_locked(&ndns->dev.mutex)
- || ndns->claim != &nd_btt->dev,
- "%s: invalid claim\n", __func__);
- ndns->claim = NULL;
- nd_btt->ndns = NULL;
- put_device(&ndns->dev);
-}
-
-static void nd_btt_detach_ndns(struct nd_btt *nd_btt)
-{
- struct nd_namespace_common *ndns = nd_btt->ndns;
-
- if (!ndns)
- return;
- get_device(&ndns->dev);
- device_lock(&ndns->dev);
- __nd_btt_detach_ndns(nd_btt);
- device_unlock(&ndns->dev);
- put_device(&ndns->dev);
-}
-
-static bool __nd_btt_attach_ndns(struct nd_btt *nd_btt,
- struct nd_namespace_common *ndns)
-{
- if (ndns->claim)
- return false;
- dev_WARN_ONCE(&nd_btt->dev, !mutex_is_locked(&ndns->dev.mutex)
- || nd_btt->ndns,
- "%s: invalid claim\n", __func__);
- ndns->claim = &nd_btt->dev;
- nd_btt->ndns = ndns;
- get_device(&ndns->dev);
- return true;
-}
-
-static bool nd_btt_attach_ndns(struct nd_btt *nd_btt,
- struct nd_namespace_common *ndns)
-{
- bool claimed;
-
- device_lock(&ndns->dev);
- claimed = __nd_btt_attach_ndns(nd_btt, ndns);
- device_unlock(&ndns->dev);
- return claimed;
-}
-
static void nd_btt_release(struct device *dev)
{
struct nd_region *nd_region = to_nd_region(dev->parent);
struct nd_btt *nd_btt = to_nd_btt(dev);
dev_dbg(dev, "%s\n", __func__);
- nd_btt_detach_ndns(nd_btt);
+ nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns);
ida_simple_remove(&nd_region->btt_ida, nd_btt->id);
kfree(nd_btt->uuid);
kfree(nd_btt);
@@ -172,108 +122,19 @@ static ssize_t namespace_show(struct device *dev,
return rc;
}
-static int namespace_match(struct device *dev, void *data)
-{
- char *name = data;
-
- return strcmp(name, dev_name(dev)) == 0;
-}
-
-static bool is_nd_btt_idle(struct device *dev)
-{
- struct nd_region *nd_region = to_nd_region(dev->parent);
- struct nd_btt *nd_btt = to_nd_btt(dev);
-
- if (nd_region->btt_seed == dev || nd_btt->ndns || dev->driver)
- return false;
- return true;
-}
-
-static ssize_t __namespace_store(struct device *dev,
- struct device_attribute *attr, const char *buf, size_t len)
-{
- struct nd_btt *nd_btt = to_nd_btt(dev);
- struct nd_namespace_common *ndns;
- struct device *found;
- char *name;
-
- if (dev->driver) {
- dev_dbg(dev, "%s: -EBUSY\n", __func__);
- return -EBUSY;
- }
-
- name = kstrndup(buf, len, GFP_KERNEL);
- if (!name)
- return -ENOMEM;
- strim(name);
-
- if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0)
- /* pass */;
- else {
- len = -EINVAL;
- goto out;
- }
-
- ndns = nd_btt->ndns;
- if (strcmp(name, "") == 0) {
- /* detach the namespace and destroy / reset the btt device */
- nd_btt_detach_ndns(nd_btt);
- if (is_nd_btt_idle(dev))
- nd_device_unregister(dev, ND_ASYNC);
- else {
- nd_btt->lbasize = 0;
- kfree(nd_btt->uuid);
- nd_btt->uuid = NULL;
- }
- goto out;
- } else if (ndns) {
- dev_dbg(dev, "namespace already set to: %s\n",
- dev_name(&ndns->dev));
- len = -EBUSY;
- goto out;
- }
-
- found = device_find_child(dev->parent, name, namespace_match);
- if (!found) {
- dev_dbg(dev, "'%s' not found under %s\n", name,
- dev_name(dev->parent));
- len = -ENODEV;
- goto out;
- }
-
- ndns = to_ndns(found);
- if (__nvdimm_namespace_capacity(ndns) < SZ_16M) {
- dev_dbg(dev, "%s too small to host btt\n", name);
- len = -ENXIO;
- goto out_attach;
- }
-
- WARN_ON_ONCE(!is_nvdimm_bus_locked(&nd_btt->dev));
- if (!nd_btt_attach_ndns(nd_btt, ndns)) {
- dev_dbg(dev, "%s already claimed\n",
- dev_name(&ndns->dev));
- len = -EBUSY;
- }
-
- out_attach:
- put_device(&ndns->dev); /* from device_find_child */
- out:
- kfree(name);
- return len;
-}
-
static ssize_t namespace_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
+ struct nd_btt *nd_btt = to_nd_btt(dev);
ssize_t rc;
- nvdimm_bus_lock(dev);
device_lock(dev);
- rc = __namespace_store(dev, attr, buf, len);
+ nvdimm_bus_lock(dev);
+ rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
dev_dbg(dev, "%s: result: %zd wrote: %s%s", __func__,
rc, buf, buf[len - 1] == '\n' ? "" : "\n");
- device_unlock(dev);
nvdimm_bus_unlock(dev);
+ device_unlock(dev);
return rc;
}
@@ -324,7 +185,7 @@ static struct device *__nd_btt_create(struct nd_region *nd_region,
dev->type = &nd_btt_device_type;
dev->groups = nd_btt_attribute_groups;
device_initialize(&nd_btt->dev);
- if (ndns && !__nd_btt_attach_ndns(nd_btt, ndns)) {
+ if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
dev_dbg(&ndns->dev, "%s failed, already claimed by %s\n",
__func__, dev_name(ndns->claim));
put_device(dev);
@@ -342,30 +203,54 @@ struct device *nd_btt_create(struct nd_region *nd_region)
return dev;
}
-/*
- * nd_btt_sb_checksum: compute checksum for btt info block
+static bool uuid_is_null(u8 *uuid)
+{
+ static const u8 null_uuid[16];
+
+ return (memcmp(uuid, null_uuid, 16) == 0);
+}
+
+/**
+ * nd_btt_arena_is_valid - check if the metadata layout is valid
+ * @nd_btt: device with BTT geometry and backing device info
+ * @super: pointer to the arena's info block being tested
*
- * Returns a fletcher64 checksum of everything in the given info block
- * except the last field (since that's where the checksum lives).
+ * Check consistency of the btt info block with itself by validating
+ * the checksum, and with the parent namespace by verifying the
+ * parent_uuid contained in the info block with the one supplied in.
+ *
+ * Returns:
+ * false for an invalid info block, true for a valid one
*/
-u64 nd_btt_sb_checksum(struct btt_sb *btt_sb)
+bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
{
- u64 sum;
- __le64 sum_save;
-
- sum_save = btt_sb->checksum;
- btt_sb->checksum = 0;
- sum = nd_fletcher64(btt_sb, sizeof(*btt_sb), 1);
- btt_sb->checksum = sum_save;
- return sum;
+ const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
+ u64 checksum;
+
+ if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
+ return false;
+
+ if (!uuid_is_null(super->parent_uuid))
+ if (memcmp(super->parent_uuid, parent_uuid, 16) != 0)
+ return false;
+
+ checksum = le64_to_cpu(super->checksum);
+ super->checksum = 0;
+ if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
+ return false;
+ super->checksum = cpu_to_le64(checksum);
+
+ /* TODO: figure out action for this */
+ if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
+ dev_info(&nd_btt->dev, "Found arena with an error flag\n");
+
+ return true;
}
-EXPORT_SYMBOL(nd_btt_sb_checksum);
+EXPORT_SYMBOL(nd_btt_arena_is_valid);
static int __nd_btt_probe(struct nd_btt *nd_btt,
struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
{
- u64 checksum;
-
if (!btt_sb || !ndns || !nd_btt)
return -ENODEV;
@@ -375,14 +260,8 @@ static int __nd_btt_probe(struct nd_btt *nd_btt,
if (nvdimm_namespace_capacity(ndns) < SZ_16M)
return -ENXIO;
- if (memcmp(btt_sb->signature, BTT_SIG, BTT_SIG_LEN) != 0)
- return -ENODEV;
-
- checksum = le64_to_cpu(btt_sb->checksum);
- btt_sb->checksum = 0;
- if (checksum != nd_btt_sb_checksum(btt_sb))
+ if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
return -ENODEV;
- btt_sb->checksum = cpu_to_le64(checksum);
nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL);
@@ -416,7 +295,9 @@ int nd_btt_probe(struct nd_namespace_common *ndns, void *drvdata)
dev_dbg(&ndns->dev, "%s: btt: %s\n", __func__,
rc == 0 ? dev_name(dev) : "<none>");
if (rc < 0) {
- __nd_btt_detach_ndns(to_nd_btt(dev));
+ struct nd_btt *nd_btt = to_nd_btt(dev);
+
+ __nd_detach_ndns(dev, &nd_btt->ndns);
put_device(dev);
}